The invention relates in general to an indicating device for the elevators of a group of elevators and, in particular, to indicator elements at the floors which indicate to the passengers waiting at the floors whether the desired destination floor can be reached with an arriving car.
U.S. Pat. No. 3,374,864 discloses a group elevator control in which the desired destination floor can be entered at the floor of entry. For this purpose, call buttons for every floor are arranged at the floors, while no call buttons are provided in the car. The control operates in such a manner, that the car specified for a destination floor indicates, on arrival at the floor of entry, the destination floor number by means of an optical indicating device so that passengers will not enter erroneously who wish to go to other destination floors. In this group control conceived for three floors and two elevators, the indicating device has to indicate solely the numbers of two floors, which can be easily comprehended by waiting passengers. For larger installations with many floors, an indicating device of this type has to be designed for the appropriate number of floors, so that the reading of the indicating device, especially in case of heavy traffic and cars of great capacity, will demand increased attention of the passengers, will take longer and will make rapid entrance decisions impossible.
On elevators with call buttons arranged in the car, as described for example in the German document No. 1 773 352, open for inspection, it is known to arrange directional arrows above or near the floor door, which light at the arrival of a car at a floor and indicate the direction of the continuing trip. Such indicating devices make it known to the waiting passengers at a first glance, whether the continued travel direction of the car corresponds with desired direction of travel, so that rapid entrance decisions can be taken. However, this type of indication is not suited for controls according to the above described art.
The problem is to create an indicating device for group elevator controls in which passengers waiting on a floor are able to recognize, without effort, even in the case of larger elevator installations and heavy traffic, whether the calls entered by them for destination floors have been assigned to an arriving car.